1. Field of the Invention
The present invention relates generally to a security system for securing an enclosed structure, and more particularly to a lock assembly forming part of the security system.
A security system with a distinctly different type of lock assembly and an enclosed structure, such as a cabinet or a cart, in which the security system can be incorporated are disclosed in commonly assigned U.S. Pat. No. 5,647,650, which is incorporated herein by reference.
The lock assembly of the present invention is ideally situated for use in an enclosed structure and security system as shown in FIG. 1. In that figure, an enclosed structure 10 includes four flanged support posts 12 for supporting two exterior side panels 14 and an unshown back panel. Interior side panels 16 are disposed side-by-side adjacent to the exterior side panels. Top and bottom platforms 18 and 20, respectively, complete the basic components of the enclosed structure. The completed structure forms a 3-sided enclosed frame, with the front side, or fourth side, open to slidably receive an array of drawers, shelves, etc.
Each interior side panel 16 includes a corrugated interior surface 21 with an array of corrugations 23 adapted to receive the drawers, shelves, etc. The horizontal corrugations are uniformly spaced in the vertical direction. Small, semicircular openings 25 can be seen in the lateral front face of the interior side panel immediately below the end of each corrugation. The openings extend to the underside of each corrugation but cannot be seen in this view. The openings allow locking fingers, which will be positioned in the corrugations as discussed below, to move in and out of the corrugations as part of the security system.
A main component of the security system of the '650 patent is an elongated locking bar 22 as shown in FIG. 2. The locking bar is equipped with a plurality of flexible locking fingers 24, or locking members, secured along its length. The locking bar 22 is positioned in an elongated recessed pocket 27 in the interior side panel 16 as shown in FIG. 3. When the locking bar is in position, each locking finger will be located in a corrugation of the interior side panel.
With reference to FIG. 4, each locking finger includes a lateral arm 26 and an angular tip 28. The angular tip 28 is formed to have an angled face 32 spanning an abutting face 34 and a front face 36. As seen in the figure, the lateral arm is angled and extends from a base plate 29, which is affixed to the locking bar.
A partial front view of the corrugated side panel 16 with two locking fingers 24 is shown in FIG. 5. In this figure, the locking fingers 24 extend through the openings 25 in the underside of the corrugations 23, and are thus in their locked position. In the locked position, the locking fingers will engage a notched channel or other corresponding element in a sliding frame of a drawer, tray, door, etc., and prevent it from being withdrawn. In this locked position, however, the shape and flexibility of the locking finger allows for an open drawer to be fully inserted and locked. More specifically, the angled face of the finger tip permits the sliding frame to impart an upward force to the locking finger, which in response will flex upwardly and allow the drawer to continue sliding until the notched channel receives the finger tip. At this point the locking finger will return to its unbiased state and lock the drawer.
2. Description of the Prior Art
In the security system disclosed in the '650 patent, the enclosed structure is secured (locked) and unsecured (unlocked) by directly engaging the locking bar. Lifting the locking bar raises the locking fingers out of the openings and unlocks the enclosed structure. In one embodiment, a cam 31 engages the locking bar from below as shown in FIG. 3. The cam is rotated by an electric motor 33 to raise and lower the locking bar. In another embodiment, a mechanical locking mechanism employs an S-shaped link that is connected to a top portion of the locking bar. A pin operated by a key lock engages and rotates the link to raise and lower the locking bar.
However, further improvements in a security system for an enclosed structure are desired. For example, it is desirable to provide a lock assembly with increased versatility and mobility, allowing it to be positioned at any desired height position in the enclosed structure and easily added or removed therefrom.